Garmin Support


Most of the information on this page is my personal opinion based on experience. The answers and suggestions that you get from a Garmin technician may differ from mine. But my opinion is that when troubleshooting your Garmin GPS system if you have lost the signal on your dog:​​

  1. First, check to see if the light on your DC20, DC30, DC40 or TT10 is flashing one, two or three times consecutively. One time indicates that you do not have a GPS signal and therefore the collar is not sending a signal to your receiver. When you first power your collar on, it will blink one flash at a time. After it acquires a signal from at least three satellites (which should take about a minute or so) the light on the collar will blink in a series of two. If the collar has any obstructions from the sky (such as a metal roof on a dog box) it may not acquire a signal. At the time that the light starts the two-blink series the collar will start sending a signal revealing its location to your receiver. When the collar receives a signal from at least seven satellites it will start blinking in a three flash series. It is a good habit to make sure that you have picked up the three-blink series before turning your dog loose. (Especially a running type hound that covers a lot of area at a run). Sometimes a three-blink series will change to a one or two-blink series when the collar is inside the dog box. When this happens a dog can be turned loose with a weak signal or no signal and the dog cannot be located until he stops long enough that the collar regains the signal. (Sometimes I have seen situations where the dog stops and still does not acquire a signal). If you have been careful to acquire a three-blink series before turning the dog loose and still have lost signal, you may be dealing with a bad GPS antenna. On a DC30 or a TT10 it could be the wire that leads to the GPS antenna that is damaged. If this is the case, you will need to replace the damaged antenna or wire.
  2.  The second thing to check is the antenna that is used to send the signal from your collar to your receiver. The best way to check the antenna is to switch it out with a new one or one-off of a different collar that you know is tracking properly. The range that your unit will track will vary depending on the type of terrain. Garmin has rated the Astro 220 at 7 miles and the Astro 320 and the Alpha 100 at 9 miles. Very seldom if ever will you actually attain these distances. It is a very good idea to test a new system or a system that you know is working properly in an area that can be used as a test area. Later, when a system is not working properly, you can try it in the test area and you will know what kind of distance to expect. To set up the test area, the test should be done with factory antennas from Garmin, which in my opinion will out track any of the aftermarket antennas on the market. The one exception is the aftermarket magnetic mount antenna for vehicles, of which some will track slightly farther than the one from Garmin. There are several aftermarket cable antennas on the market. I have had several customers who have installed these cable antennas to increase the range. By doing this, more often than not, they actually decrease the range. The aftermarket antennas are more durable but you will find more inconsistency among the aftermarket antennas than you will with the Garmin brand antenna. Some aftermarket antennas may track as far as the Garmin antennas, but don't be fooled into thinking that because it is marketed as "Long Range" that it is as good as the factory antenna. If you really want to know if it is as good as it should be, try it out in your test area.
  3.  The next thing to check is interfering frequencies.  This can be a hard thing to determine but here are some examples I have seen:
    • ​Other hunters who have the same ID number as one of your collars. I have had guys tell me that it can not be interfering ID numbers due to the fact that they have a pin number entered in their collar. A pin number will help with interfering collars but if two units with the same ID are near enough for your receiver to pick up a signal, it will cause both of the units to decrease range to as little as a couple of hundred yards or less. It is very important that you know what the ID number is from other collars that will be around you during your hunt so that you can be sure that none of them have the same ID numbers that you do. The danger is, if two dogs are turned loose with the same ID number and your dog never gets nearer than the dog with the conflicting unit, you may never be able to track him until he is completely out of range of your receiver and is lost.
    • Another interfering frequency that I have seen is that the DC30 or DC40 collars are limited to a range of just a few hundred yards when the dogs that have the TT10 collars come near the Astro. This can happen when the interfering dogs come near during the hunt or if a hunter drives up with them in the back of his truck. If this happens to you, try to get away from the interfering TT10s until you can get a signal. You may even have to ask someone to power off his TT10's so that you can retrieve your dog. I have heard of the DC30 or 40 doing the same to an Alpha 100 but I do not seem to be as common.
    • One scenario that does not seem to happen very often is when a telemetry collar interferes with a GPS system. I had a customer who bought a Garmin system but wanted to leave his telemetry collar on the dogs along with the GPS. For a couple of months, he would complain about the limited range. He was only able to track 300-400 yards at best. After troubleshooting with him I began to think that it was somehow user error. Finally, I asked him to try it without the telemetry collars but having NO faith in the Garmins he refused until one day he hung the collars on the fence and drove away. One time with the telemetry collars on and one time with them off. With the telemetry collars on he could only track about 300 yards and when he turned the telemetry off e could track about 3 1/2 miles. We do not know it the telemetry was interfering with the satellite signal or the signal fro the collar to the receiver but he changed telemetry frequencies and had no more problems.
    • To help you find a frequency interference problem, a list from Garmin of the frequencies used on the DC20,30 and 40 is as follows:
      ID 0-9 start at 151.820
      ID 10-19 start at 151.880
      ID 20-29 start at 151.940
      ID 30-39 start at 154.570
      ID 40-49 start at 154.600
    • I do not know for sure but I have been told that the TT10s are in that same range but to my understanding, the frequencies on them fall between the DC20,30 and 40 ID frequencies
  4. If we still have not found the problem, you may need to update your software.  Garmin techs will tell you to do this first but they have more faith that it will fix your problem than I do, although I have had an updated work on an occasional tracking problem.  One of these times was when the DC40 first came onto the market.  They did not work well at all.  In fact, I sent my first shipment back after trying to hunt with them.  Shortly after that, the techs at Garmin told me that I should have updated my units.  Having no luck up until then with updates I was skeptical.  Much to my surprise though the update worked. The DC40 was still not as good as the DC30 at maintaining a GPS signal (GPS fix) but it was good enough to keep up with most types of dogs.  The exception at that time was the DC40 would still lose GPS signal on running hounds that run for several hours.  Since then Garmin has come out with several updates and I like the DC40 better than the DC30 now.  Occasionally we still have problems with the DC40 maintaining a signal on running hounds, especially in the areas that have dense foliage and it seems to be worse after rain or in wetland type areas.  I do recommend and update once in a while.  Just click on this link to update your unit.

  • can really be beneficial at times especially on new products for example, at the time of this writing  Alpha 100 is still fairly new on the market.  I have seen several problems with the Alpha/TT10s repaired by doing an update on them.  Also as new collars are introduced you will need to update to accommodate the new equipment. This can really be beneficial at times especially on new products for example, at the time of this writing the Alpha 100 is still fairly new on the market.  I have seen several problems with the Alpha/TT10s repaired by doing an update on them.  Also as new collars are introduced you will need to update to accommodate the new equipment.


Update the Astro using web updater and then use the following instructions to target each of the collars for update. On the Astro, select DOG INFO, press MENU once, then select UPGRADE DOG UNIT. Then run WEBUPDATER against the astro again to update each of the collars. If you have an Astro 320 that has the current software on it you can do this in the field without a computer because the Astro 320 has unit to unit transfer. Just do the following on the Astro 320. Press the DOG button, then select a specific dog and press enter. Then press MENU and select UPGRADE DOG UNIT press ENTER and follow the prompts.


It generally helps to disconnect the antenna on the collar for five minutes to reset it. This should be done with the collar still powered on. On both Dc30 and 40 units you remove the plate that holds the collar to the main body of the unit and pull the collar aside. While you have the collar off be sure to write down the serial number in case the unit can not be reset and has to be exchanged. On DC 30 units the number starts with 1DW on DC40 it begins with 215. On the DC40 units there is a screw under the weather cap which will have to be removed. On the DC30 units there is no screw holding the wires in place. On the DC30 units there are two wires and you want to disconnect the smaller one. If you are still having trouble with tracking range continue to the next step. In all cases, check the connections for corrosion and if there is any clean it up before reassembly.


**Try this before the Master Reset, it will clear bad satellite data without deleting you dog collars from the unit.**
Power the unit off and hold down on the OUT button while the you power the unit on. Wait a few minutes for the Astro unit to reacquire satellites and then try your unit to see if this fixed it. If your unit is still not tracking normally do the Master Reset procedure shown below. NOTE when you take your unit out for test it may be a good idea to START NEW HUNT.


With the unit turned off press and hold the MAP+ENTER+POWER buttons. Answer YES to the question "Do you want to erase all user data?
Now press enter and allow the device to fully boot up. This resets the unit to factory defaults.


DC collars utilize the LED to provide feedback to the device's status. DC20 and DC30 will show a solid blue light while charging and the light will turn red when charging is complete. DC40 will show a flashing blue light while charging and a solid blue light when charging is complete. A red blinking light indicates the collar is on and ready for use. If a DC20,30 or 40 is displaying a solid red light the firmware in the collar will need to be reinstalled with the Astro.

  • To reinstall firmware utilizing an Astro 220:
    1. Turn the DC collar off
    2. Power on your Astro
    3. Connect Astro to a computer via USB cable.
    4. Ensure Astro and DC collar are paired
    5. Press DOG
    6. Press MENU
    7. Select DOG LIST from list of options
    8. Select desired dog collar and press ENT
    9. Select SHOW INFO from list of options
    10. Press MENU
    11. Press UPGRADE DOG UNIT from list of options
    12. Wait for Astro to search for the DC collar
    13. Press and hold the power button on the DC collar
    14. While you continue holding the power button on the DC collar run WEBUPDATER
    15. Wait for software update to progress (status bars will move across screen)
    16. Release power button

  •  To reinstall firmware utilizing an Astro 320:
    1. Turn off DC collar
    2. Power on Astro
    3. Ensure your Astro and DC collar are paired*
    4. Connect Astro to a computer via USB cord
    5. Launch Web Updater
    6. Click next on Web Updater welcome screen 
    7. Click Find Device
    8. Click next once Web Updater finds Astro
    9. Update Astros software, if needed
    10. Select next to look for additional updates
      • If an update for the DC collar appears, check the box to select update
        Click next to send dog collar update to Astro
      • If no update for DC collar appears to proceed to the next step
    11. Disconnect USB and power up Astro
    12. Press DOG
    13. Select dog needing update
    14. Select SHOW INFO
    15. Press MENU
    16. Press and hold the power button on the DC collar
    17. Select UPGRADE DOG UNIT on the Astro after the DC collar light turns solid red
Continue holding the power button on the DC collar until Astro indicates the software is up to date
After the software is finished loading, the DC collar will work as normal.
* If collar has been removed from the Astro 320 it is possible to pair the two even when there is a solid red light. This is not possible with the Astro 220.

  • To pair a collar with a solid red light to the Astro 320:
    1. ​Turn all collars off
    2. Power on Astro
    3. Press DOG
    4. Press MENU
    5. Select DOG LIST
    6. Select ADD DOG
    7. Select NO when asked, "Are you able to touch the handheld to the new dog unit?"
    8. Select YES when asked, "Do you know the dog unit ID?"
    9. Select any available number
    10. Enter a name
    11. Select DONE
It will now be possible to proceed with the firmware reinstallation for the collar.


If you are having trouble with a unit that is not under warranty and the troubleshooting tips above have not worked you may want to send it in for service. We are able to fix some problems here at our store in Middletown call us and let us know what problem you are having we will let you know if we think we can fix it. Sometimes we can fix things cheaper than the flat rate that Garmin charges. Our phone number is 573-549-2888. To contact Garmin to have your unit serviced call 1-800-800-1020.